Steers like Crap

don't ignore idler mount on k-frame either.
"Square" shoulders on tires can contribute to "nibbling" on road seams. Back when we had nothing but bias, and bias-belted tires in the 60''s and early 70''s we REALLY had to deal with that nibbling problem. The advent of wider, low profile tires did nothing to help that problem.
I'd double check your lower ball-joints, too. I've seen brand new lowers with excessive slop in them. Also if any of your steering linkage ball joints have ANY play in them, your toe will be changing. You should NEVER have toe-out. I like to run a little toe-in, so at worst you'll have zero at speed.
I agree with posters, don't expect rack & pinion road feel.